Recently, the age where the web is used to simply show information to a user has changed into a new age where the software of a user receives a result so as to automatically process a lot of tasks. When a web service technology is applied to various services such as electronic commercial transaction and information searching which are currently achieved on the web, a lot of tasks which have not been automatically processed so far can be automated. Then, it is possible to maximize the productivity and effectiveness of information systems as well as the convenience of users.
Recently, the structure of information existing on the web is being changed. That is, information having a new form, which can be analyzed and processed by computers, is being added to the existing information. The information is referred to as meta data. When the meta data is added into the current web, computers can analyze the meaning of information through the meta data and processes the information, which is referred to as ‘Semantic Web’.
Particularly, when the Semantic Web is applied to electronic commercial transaction, a lot of tasks which have not been able to be processed can be automatically processed. In a typical type of Internet shopping, a purchaser visits Internet shopping malls, sees products, and selects a product to purchase. On the Semantic Web, however, meta information on a product standard, a transaction condition and the like as well as product information is provided in each Internet shopping mall. In such an environment, computers can perform price negotiation as well as searching of a desired product in place of people.
The Semantic Web can be effectively utilized in a B-to-B system integration field and a value-added searching field as well as in the electronic commercial transaction. Further, the Semantic Web is considered to be a core technology which can change the paradigm of information communication in the near future.
In the existing web service, the WSDL (Web Service Description Language) based on XML (extensible Markup Language) is used. In the Semantic Web service, however, a web service description language such as DAML-S (DAPRA Agent Markup Language-Service) based on an ontology language is used. Researches on the Semantic Web service are performed in view of web service searching, web service driving, web service configuration, web service execution monitoring and the like. Particularly, the Semantic Web service searching is a base field for achieving an ultimate purpose of the Semantic Web service and has different features from the existing information searching. That is, a storage system and a searching method are required, which are suitable for the Semantic Web description language.
Conventionally, attempts to use a DMBS in the Semantic Web service have been made at a research level once in a while. In such attempts, however, the DMBS serves as only a storing place. Therefore, the DMBS is not closely combined with the overall information flow including knowledge creation, knowledge extension, and knowledge provision.
In conventional similar systems for the Semantic Web service, the DMBS is partially utilized, which means there is a limit in the performance of inference service.
Accordingly, in the present invention, the overall process of creating an inference result from an ontology schema is consistently constructed so as to maximize the performance.